| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting device which has a plurality of LED modules connected thereto and is capable of selecting one of them to thereby eliminate the need for replacing the LED modules until the end of the service life of the device. <P>SOLUTION: A lighting time counter 5 stores a preset setting time, and counts and stores a cumulative lighting time of a selected LED module electrically connected to a step-down circuit 3 and a battery 9 via a load connection switching circuit 11. An output control circuit 6 makes the step-down circuit 3 turn on the selected LED module when power is supplied from a commercial power source 1, and makes the battery 9 turn on the selected LED module when the power supply from the commercial power source 1 is cut off. Also, when the cumulative lighting time of the selected LED module measured by the lighting time counter 5 exceeds the setting time, the output control circuit 6 makes the load connection switching circuit 11 select another LED module, which is different from the selected LED module, as a newly selected module so that it is electrically connected to the step-down circuit 3 and the battery 9. <P>COPYRIGHT: (C)2012,JPO&INPIT |
